So when I checked the RMT, I saw it filled with teams that had cores inside. It brought me to try to make my own cores that I discussed with Faked Thrower yesterday night. Smogon may have their own cores, but it doesn't mean we can't find cores that work efficiently. So many unexperienced members of this site may ask: What is a core? Smogon has this covered, providing an awesome explanation.

A core consists of 2-3 Pokémon that work well together through Defense, Offense, both, or through other ways to counter most of the metagame. This makes having a solid core one of the most important parts of team building. - Smogon University

Now, there is a lot of different types of cores. Smogon has this covered as well.

There are four different types of cores and they are as follows:

Defensive: This core consists of 2-3 Pokémon that compliment each other defensively. They are designed to counter a wide range of
threats through bulk and synergy, while taking resisted and neutral
hits with relative ease.

Offensive: This core is made up of Pokémon that have great coverage and power so that they can take out a wide range of threats
in the tier.

Mixed: This core consists of Pokémon that synergize well both offensively and defensively. For this type, you may have two walls and
one offensive Pokémon that all have great synergy and work well
together.

Other: This includes Pokémon who work together in other ways. Like a Toxic Spikes user and a Substitute + Calm Mind sweeper. Or a Spiker
and a Pokémon with a lot of power but not enough to break through
walls without Spikes. Even a lure and a sweeper can count as a
combinations. - Smogon University

So I was thinking we could post our favorite cores on this Q! If you post, please include EVs, Natures and everything else in a full moveset. Also, include what type of core yours is (Offense, Defense, Mixed or Other) and in what tier your core can be used and performs the best. Add a short description explaining your core. I'll be posting a core just to show the format in which you should answer.

Darmanitan-Z

+

Roserade

This is an Offensive core for use in the UU Tier. Darmantian-Z and Roserade provide great offensive synergy while Darmanitan can use Belly Drum to safely render himself to Zen Mode. BLA BLA BLA.

To note that that was an example and you should put a bigger description. xD

Remember, there is no such thing as a perfect core. Don't get too arrogant about your core and saying that, for example, your Leavanny could own your Dialga. Make a usable core, meaning no gimmick such as Specs Delibird or Banded Blissey. I hope you guys will post your cores here so everyone who visits this Q will get ideas for new cores and teams.

Have fun posting your cores and DO NOT post Smogon cores, we can just go see them there.

29 Answers

Scizor + Rotom - W.

Scizor (M) @ Life Orb / Leftovers

Trait: Technician

EVs: 80 HP / 252 Atk / 176 Def

Adamant Nature (+Atk, -SAtk)

U-turn

Bullet Punch

Pursuit

Roost

This is an effective set for Scizor. U-Turn makes Scizor leave into RotomW. Bullet Punch is a must have on any Scizor + Technician. Pursuit adds to the power. This works great for when Rotom switches out from Volt Switch, because it forces mons out. Roost provides healing if Rotom gets KO'd. Your Lefties / Orb allows you to heal or hope he gets the job done quickly. Technician is obvious. EVs give a straight bulk as well as offensive capabilities. Nature just throws away unused stat.

Rotom @ Specs / Scarf / Toxic Orb

Trait: Levitate

EVs: 4 Def / 252 SAtk / 252 Spd

Timid Nature (+Spd, -Atk)

Hydro Pump

Thunderbolt

Trick

Volt Switch

Hydro Pump is your basic STAB. Thunderbolt is used to cover those annoying Fighting + Water types, and offers a nice secondary STAB. Trick is used to give a hurtful item away. Volt Switch allows you to return back to Scizor. Specs should be the item since Rotom is so frail, but the other ones might be worth your while. EVs give Rotom sweeping speed that he needs. Nature, once again, throws away useless stat.

How it works:

Scizor resists everything Rotom is weak to, and Rotom resists everything Scizor is weak to. Simple. This takes some serious timing + skill to pull off, but if you have it you are good to go. Just switch these guys back and forth. This puts some serious pressure on the opponent. Be sure to run a Spinner, because Hazards will naturally threaten this core. They work unbelievably well together. I highly recommend this one. If you want me to classify this one, it would probably be an "other" core.

Simple. An offensive core that works pretty well. The reason why these two work well together:

They cover each other's main weaknesses well. Barring Rock, of course.

They act as lures for each other. Gyarados lures in Electric moves for Jolteon to absorb, and Ground moves aimed at Jolteon can be rendered useless by Gyarados' Flying type. After being lured in, especially with Choiced Pokemon, they can sweep the opponents.

..Your what? Stunfisk is in NU for a reason. It's pathetic and looks like a pancake with eyes. I'm not even sure if Discharge would OHKO Gyarados, who could reply with Waterfall. Even if he didn't resist, Jolteon could OHKO with HP Ice. End of discussion.

Hey, look, Yellow. NOBODY would switch in his Gyarados on a Stunfisk, K? So I assume you didn't lead with Stunfisk. Even without a boost, I use Waterfall, you switch-in your Stunfisk, he resists, and then I KO. Also, no one uses Stunfisk in OU.

With the right switching, you would lose a turn. Try and use TBolt on Gyarados, I switch to Jolteon. You use Earth Power, I switch into Gyarados. You try and predict and use Earth Power, I use Dragon Dance. Bye Bye, Stunfisk.

Btw, Stunfisks Earth Power only has a chance to OHKO Jolteon, so if it doesn't, Jolteon can use HP Ice (Which is a Garunteed 2HKO) to kill Stunfisk. Not assuming Gyarados isn't switched back in to take Earth Power, in which case Stunfisk is royally screwed.

OU ChandyThorn Tanking

This is quite a fun one to play with. The way it works is very simple.

Ferrothorn is resistant to all of Chandelure's weaknesses excluding than ground.
Chandelure is IMMUNE to Ferrothorn's weaknesses, and is boosted by Fire.

This allows Ferrothorn to be used in Sun. Sun provokes people to use Fire STABs on Ferro, but Chandy gets boosted by it.

Hex (Chandelure) @ Choice Specs

Trait: Flash Fire

EVs: 252 SAtk / 252 HP / 4 SDef

Modest Nature

Shadow Ball

Trick

Will-O-Wisp

Energy Ball

This set makes an excellent wall, effectively screwing physical attackers like Terrakion, DNite, and Infernape. Hell, if you can Trick off an Air Balloon you are in top shape. Anyways, this Chandy can be used as a lead or switch-in to fighting. As a lead, Shadow Ball combined with Specs is an excellent STAB, hitting OU's psychics hard, as well as Jelli. Trick is an effective shut down to Fighting sweepers, very common in OU. Terrakion is a notable threat, He would simply OHKO Ferro. If it is Ballooned, Chandy is in a bind. I can see EQuake on Chandy, but if he goes for a Dance or Rock Polish Chandy is lucky to lock him in and pick off one of the weaknesses. After doing so, Chandy completely shuts it down with a Will-O-Wisp. For the stuff like Gastro, Energy Ball is an excellent coverage, most likely an OHKO if Flash activates.

Ferrothorn @ Leftovers

Trait: Iron Barbs

EVs: 252 Def / 252 HP / 4 SDef

Impish Nature

Leech Seed

Protect

Power Whip

Thunder Wave

Ferrothorn... such a beautiful wall, but easily shut down by Focus Miss and Fire Blast. Both of which Chandy negates :D. Not much to say here. Ferro can switch in on Chandy's weakness, allowing free moves. Ferro can expect a switch to a special FBlast user, allowing a free move. With that free move, Ferro can throw in a Leech Seed, allowing some nice healing. Focus Miss will likely come. LOL, suck on Protect. Naturally some players are persistent, and will try again. THAT is when Ferro switches. Leech Seed give Chandy healing. When annoying stuff like Poli comes in, Ferro can switch in. Power Whip is brute force, KOing all the annoying waters and hippos. When an annoyance like Heatran comes in, Thunder Wave allows both members of the core to troll much easier.

Regimoonguss > Alomomoonguss. Just sayin'. Anyway, this core is one I fell in love with in NU. It uses Bulky Regirock & Specially Defensive Amoonguss. Regirock, even uninvested, can tank physical hits with ease due to his 200 (TWO HUNDRED!) base defense stat. Amoonguss on the other hand uses its great base HP and solid SDef, along with Regenerator, to comfortably wall a lot of Pokemon that give Regirock trouble. Regirock can set up Stealth Rock, racking up residual damage with the many switches the core forces. It can also paralyse opposing Pokemon, making them easier dealt with by other team members. Stone Edge and Drain Punch are two high power moves with great coverage. Amoonguss has access to Spore, which can potentially cripple a Pokemon for the rest of the game. Giga Drain provides healing along with a reliable STAB move. Clear Smog stops most setup sweepers in their tracks, while HP Ice is coverage, but can be replaced with Foul Play or Stun Spore.

Now you may be thinking that those sets seem a little wierd, like maxing SAtk on Girstina just for Draco Meteor, but Giratina is insanely bulky even without investment and his Draco Meteor hits like a runaway train. Giratina takes Fire moves for Forry and Forry takes Dark, Ghost, Ice, and Dragon moves for Giratina. Giratina then uses Dragon Tail to phase the enemy down, eventually using Shadow Sneak to pick off weakened opponents. Will-O-Wisp is useful for crippling the foe's sweepers, and Draco Meteor is for bringing the pain. Giratina-O could be substituted for a regular Specially Defensive double phase Restalk Giratina as well. This core appreciates fellow phazers and rain, although neither of those are essential.

This is a combination of both Tentacruel and Gliscor. This Defensive core covers all their weaknesses (besides Psychic) and works pretty well. Gliscor stalls out Pokemon and provides Stealth Rocks for the team, and is immune to Ground and Electric moves, which Tentacruel is weak to. Tentcruel provides Rapid Spin, as well as Toxic Spikes for the team, and takes Water and Ice moves that Gliscor despises. And conveniently, Gliscor is a Physical wall, while Tentcrual is a Special wall.

Basic. Genesect can U-turn out to Dugtrio on threats. If a Heatran wants to come out on Genesect, Dugtrio can come in and destroy it. Rotom-H falls to Stone Edge.
Basically, Dugtrio shreds Genesect's counters, leaving Genesect to sweep.

The core that is quite popular in lots of Sand teams. Landorus-T gained the wonderful ability Intimidate, which helps Physical attacks. Further, Landorus-T and Genesect make a U-turning offensive core that is pretty hard to play against unless you get lucky and predict correctly. Genesect always had trouble taking down Heatran. While HP Ground helps, Air Ballooners bypass this. Genesect U-turns out to Landorus, and Lando can deal with Heatran. Or U-turn again, providing offensive momentum to the team. They cover the entire tier really well. One might opt to use Giga Drain over HP Ground on Genesect to nail Gastrodon.

Recently I have developed a core and it has been working well for me so far. It is a mixed, 3 Pokemon core and I call it SlowBlissSciz. If you haven't already geussed that's Slowbro, Blissey, and Scizor.

Slowbro takes the physical hits, including Fire moves directed at Scizor, and Fighting moves directed at Blissey. Blissey takes the special moves such as Electric moves aimed at Slowbro and special Fire moves targeting Scizor. Scizor is the offensive Pokemon of the 3 and his job is to sweep once Slowbro and Blissey have frustrated and crippled the opposition via Thuner Wave, Stealth Rock, and Toxic. Scizor also takes Grass and Bug moves trying to catch Slowbro. The core has some trouble with Infernape but for the most part Slowbro counters Infernape save U-turn, which Slowbro can still tank without too much trouble. For Scizor, if you are running a Choice Band set use the moves in bold when the option is given.

Choiced Salamence can rip through almost everything with STAB outrage and moxie. Steel types prove to be a problem for him though. Magnezone is there too trap those steel types and safely dispose of them with HP fire. If Heatran comes in, Magnezone's biggest threat, he'll just volt switch to safety, as his speed investment should outspeed the standard heatran. Then safely dispose of Heatran, and you won't have anything stopping Salamence.

I use dragon gem because it gets momentum straight and KO's most Pokemon regardless of type. Jirachi has lots of choice, but should retain at least an ice type move and a steel type. Other than that feel free to do what you like! Jirachi has many resistances,including ice,dragon and rock. However , it is weak to ground and fire. If only there was a Pokemon that was resistant to these types...oh, Salamence! This constant annoying and demolishing of opponents team is truly epic! Of course you can switch Salamence for Draconite, as they have the same typing. Pretty powerful, eh?

LatiThorn Core

I wanted to try Rocky Helm on Ferro, even though it is outclassed by Lefties. It takes a lot of people by surprise actually when they get the double recoil. Leech Seed is my main recovery when using Rocky Helmet.

Calm mind is to go with the Nature....... xD It gives me a massively special defense boost and an added bonus for those special moves. Roost is recovery when I'm low on HP and need more than what leftovers can give me.
I thought about doing a Healing Wish set, but I just couldn't decide. I think it would be better to run Healing wish so here is possible (alternate) moveset

- Healing Wish
- Dragon Pulse
- Psyshock
- Thunderbolt

Meh I dunno, maybe. xD

In any case. They counter each other weaknesses, (Ferro taking neutral damage from Ice and Bug) and they both have those epic walling abilities.
These two are such a perfect couple. Essentially the only major threat is TTar, who runs Superpower and Crunch. But with double recoil from Ferro on the switch in, it's gonna hurt him just as much as it hurts me.

Cofagrigus actually works quite well as a sp. def wall, since it's sp. def isn't that shabby, and it already has Will-O-Wisp to deal with physical attackers, in addition to Mummy negating things like Technician, Guts, Sheer Force or Skill Link. It also negates set up Pokemon/ Baton Passers with Haze, which is a really useful move.

Cofagrigus will provide the Fighting immunity, Porygon2 will provide the Ghost immunity and the Dark neutrality. Por2 has enough bulk to wall a few neutral moves as well as deal some pretty substantial damage with Analytic.

Blissey/ Chansey will also work in place of Porygon2, but that'd have to OU and it would mean that neither Pokemon would be able to deal much damage (unless you Toxic stall).

OU offensive core: Weavakazam

This offensive core is quite powerful. It is very potent and works very well in OU:

[email protected] life orb or expert belt
Ability: pressure
EV's: 252 att/ 252 speed/ 4 hp
nature: +speed -sp att
ice punch
night slash
low kick
fake out/ ice shard
This guy was made for OU. STAB ice and dark moves. Fake out is mostly for multiscale dragonite (allowing him to take on all of the OU dragons). Ice shard is for revenge killing. Use life orb with ice shard and use expert belt with fake out.

They cover each other awesomely. Sigyliph deals with bug and fighting and dark and electric is killed by absol. So sigyliph uses stored,power 3 times making a gengar shadow ball do 20%. Which also makes stored power Lethal. Air slash kills the bugs. Absol is kills dark and rock with super power. Electric will just be overpowered.
I'm going to complete this answer tomorrow.

Joltraptor

This is a core I used on my volt-turn team. It has amazing synergy:[email protected] sitrus berry
reckless
252 att/ 252 spe/ 4 hp
+spe -sp att
brave bird
close combat
double edge
u-turn
Staraptor is very underrated in OU he destroys things with his moves. Sitrus berry allows you to attack longer. Stealth rocks and recoil take their toll.

[email protected] life orb
volt absorb
252 sp att/ 252 spe/ 4 hp
+spe -att
volt switch
thunderbolt
shadow ball
HP ice
Jolteon is very fast so a strong volt switch set is great for him. His other moves are for coverage.

This core works very much like Joltdos or Gyareon (Jolteon and Gyarados), except that this is a volt-turn core. Ground moves aimed at Jolteon do nothing to Staraptor, and electric moves aimed at Staraptor heal Jolteon's HP.

This set allows jellicent to burn any threats to it or metagross. Hydro pump is more reliable than water spout if jellicent isnt full health It takes down or does serious damage to ground type Pokemon that threaten metagross. protect is to stall when the oppenent is burned or for metagross to dispose of it without threatening jellicent. recover is there to keep jellicent running for longer.

having the ability clear body ables metagross do use hammer arm without the lowering of speed. hammer arm counters dark type threats to jellicent while meteor mash usualy OHKO any ghost type threats when steel gem is used. bullet punch is to quickly finish of what jellicent may have started and earthquake is often good to use on opposing metagross.